The present invention relates to (pyrimidyl)(phenyl)substituted fused heteroaryl compounds which have cytokine inhibitory activity. The present invention also relates to (pyrimidyl)(phenyl)substituted fused heteroaryl compounds which have cGMP dependent protein kinase (“PKG”) inhibitory activity.
Cytokine mediated diseases and cytokine inhibition, suppression and antagonism are used in the context of diseases or conditions in which excessive or unregulated production or activity of one or more cytokines occurs. Examples of cytokines which are effected typically include Interleukin-1 (IL-1), Interleukin-6 (IL-6), Interleukin-8 (IL-8) and Tumor Necrosis Factor (TNF).
Interleukin-1 (IL-1) and Tumor Necrosis Factor (TNF) are produced by a variety of cells that are involved in immunoregulation and other physiological conditions.
There are many disease states in which IL-1 is implicated. Examples are rheumatoid arthritis, osteoarthritis, endotoxemia, toxic shock syndrome, acute and chronic inflammatory diseases, such as the inflammatory reaction induced by endotoxin or inflammatory bowel disease; tuberculosis, atherosclerosis, muscle degeneration, cachexia, psoriatic arthritis, Reiter's syndrome, rheumatoid arthritis, gout, traumatic arthritis, rubella arthritis and acute synovitis. Recent evidence also links IL-1 activity to diabetes.
Interleukin-1 has been demonstrated to mediate a variety of biological activities thought to be important in immunoregulation and other physiological conditions. [See, e.g., Dinarello et al., Rev. Infect. Disease, 6, 51 (1984)]. The known biological activities of IL-1 include the activation of T helper cells, induction of fever, stimulation of prostaglandin or collagenase production, neutrophil chemotaxis, induction of acute phase proteins and the suppression of plasma iron levels.
Excessive or unregulated tumor necrosis factor (TNF) production or activity has been implicated in mediating or exacerbating rheumatoid arthritis, rheumatoid spondylitis, osteoarthritis, gouty arthritis, and other arthritic conditions, sepsis, septic shock, endotoxic shock, gram negative sepsis, toxic shock syndrome, adult respiratory distress syndrome, cerebral malaria, chronic pulmonary inflammatory disease, silicosis, pulmonary sarcosis, bone resorption diseases, reperfusion injury, graft v. host rejection, allograft rejections, fever and myalgia due to infection, cachexia secondary to infection or malignancy, cachexia secondary to acquired immune deficiency syndrome (AIDS), AIDS related complex (ARC), keloid formation, scar tissue formation, Crohn's disease, ulcerative colitis and pyresis.
Monokines, such as TNF, have also been shown to activate HIV replication in monocytes and/or macrophages [See Poli, et al., Proc. Natl. Acad. Sci., 87:782–784 (1990)], therefore, inhibition of monokine production or activity aids in limiting HIV progression. TNF has been implicated in various roles with other viral infections, such as the cytomegalovirus (CMV), influenza virus and the herpes virus.
Interleukin-6 (IL-6) is a cytokine effecting the immune system and hematopoiesis. It is produced by several mammalian cell types in response to agents such as IL-1, and is correlated with disease states such as angiofollicular lymphoid hyperplasia.
Interleukin-8 (IL-8) is a chemotactic factor first identified and characterized in 1987. Many different names have been applied to IL-8, such as neutrophil attractant/activation protein-1 (NAP-1), monocyte derived neutrophil chemotactic factor (MDNCF), neutrophil activating factor (NAF), and T-cell lymphocyte chemotactic factor. Like IL-1, IL-8 is produced by several cell types, including mononuclear cells, fibroblasts, endothelial cells and ketainocytes. Its production is induced by IL-1, TNF and by lipopolysaccharide (LPS). IL-8 stimulates a number of cellular functions in vitro. It is a chemoattractant for neutrophils, T-lymphocytes and basophils. It induces histamine release from basophils. It causes lysozomal enzyme release and respiratory burst from neutrophils, and it has been shown to increase the surface expression of Mac-1 (CD11b/CD 18) on neutrophils without de novo protein synthesis.
There remains a need for compounds which are useful in treating cytokine mediated diseases, and as such, inhibit, suppress or antagonize the production or activity of cytokines such as IL-1, IL-6, IL-8 and TNF.
Parasitic protozoa are responsible for a wide variety of infections in man and animals. Many of the diseases are life threatening to the host, and in animal husbandry, can cause considerable economic loss. For example, malaria remains a significant health threat to humans despite massive international attempts to eradicate the disease; trypanosomiasis such as Chagas disease caused by Trypanosoma cruzi and African sleeping sickness caused by T. brucei are not uncommon in South America and Africa, respectively; and opportunistic infections in immuno-compromised hosts caused by Pneumocystis carinii, Toxoplasma gondii, Cryptosporidium sp. are becoming increasingly significant in the developed countries.
Coccidiosis, a widespread disease of domesticated animals, is caused by protozoal infection. In the poultry industry, coccidiosis is responsible for high levels of morbidity and mortality in the bird population and may result in extreme economic losses. The infectious agents are protozoa of the genus Eimeria. Some of the most significant avian Eimeria species include E. tenella, E. acervulina, E. necatrix, E. brunetti and E. maxima. 
In some protozoal diseases, such as Chagas disease, there is no satisfactory treatment; in others, drug-resistant strains of the protozoa may develop. A biochemical target of antiprotozoal drugs, cGMP dependent protein kinases (PKG), has been identified, the inhibition of which effectively treats protozoal infections such as coccidiosis and Chagas disease.
cGMP dependent protein kinases catalyze the phosphorylation of specific protein substrates. In the absence of cGMP the activity of these enzymes is very low. Thus, the inhibition of such PKG kinases can be lethal to the organism. There is a need for compounds that treat (or prevent by a subtherapeutic prophalactic dosing) coccidiosis, Chagas disease, and toxoplasmosis. Compounds that inhibit the PKG kinase of the infecting protozoa can be such preventive and treating compounds. Importantly, compounds that selectively inhibit the PKG kinase of the infecting protozoa without inhibiting the PKG kinase of mammalian PKG kinase would be lethal to protozoa while being safe for mammals. Accordingly, there is a need for such selective compounds for the treatment of protozoal infections such as coccidiosis, Chagas disease, and toxoplasmosis.
International Patent Publication Nos. WO 99/51233, WO 99/51232, WO 97/21704, WO 97/21703, and WO 00/04013 describe fused heteroaryl compounds that are antagonists of gonadotropin releasing hormone. International Patent Publication No. WO 96/06840 describes diaryl bicyclic heterocycles as inhibitors of cyclooxygenase-2.
International Patent Publication No. WO 98/22457 describes aryl and heteroaryl substituted fused pyrrole antiinflammatory agents. International Patent Publication No. WO 01/22965 describes substituted imidazoles having cytokine inhibitory activity. International Patent Publication No. WO 01/34605 describes substituted 2-aryl-3-(heteroaryl)-imidazo[1,2-a]primidines. International Patent Publication No. WO 01/30778 describes tiazole and imidazo[4,5-b]pyridine compounds. International Patent Publication No. WO 00/63204 describes substituted azoles.
The compounds 3-(2-Methylsulfanylpyrimidin-4-yl)-2-(3-trifluoromethylphenyl)imidazo[1,2-a]-pyrimidine:
and 3-(2-Methylsulfonylpyrimidin-4-yl)-2-(3-trifluoromethylphenyl)imidazo[1,2-a]-pyrimidine:
were described in International Patent Publication No. WO 01/22965 as intermediates in a process to make a substituted imidazole.